KR20100075612A - Crosslinker-containing adhesive compositions - Google Patents

Abstract

The present invention relates to an adhesive composition for bonding lignocellulosic substrates. The adhesive composition contains a crosslinking agent and a non-urea diluent, wherein the non-urea diluent is present in an amount of about 0.01 to about 75 weight percent based on the total wet weight of the composition and the crosslinker is essentially free of formaldehyde. . Also disclosed is an adhesive further containing an aqueous mixture of protein sources. The invention also relates to a process for preparing lignocellulosic composites using the adhesive composition of the invention, and to lignocellulosic composites prepared using the method of the invention.

Description

Cross-linking agent-containing adhesive composition {CROSSLINKER-CONTAINING ADHESIVE COMPOSITIONS}

The present invention relates to an adhesive composition for bonding lignocellulosic substrates. The invention also relates to a process for preparing lignocellulosic composites using the disclosed adhesive compositions, and to lignocellulosic composites prepared using the methods of the invention.

Wood adhesives prepared from a combination of polyamidoamine-epichlorohydrin resin (PAE resin) and soy protein are urea-formaldehyde (UF) resins, phenol-formaldehyde (PF) resins and melamine-formaldehyde (MF) resins. It has been used as an alternative to formaldehyde-containing adhesives such as US Patent Application No. 10 / 438,147. The performance of PAE-soy adhesive is considerably better than formaldehyde-containing materials. PAE / soy adhesive systems have been successfully applied in the production of hardwood plywood (Brown, Valerie J., "Better Bonding with Beans" in Environmental Health Perspectives, 113 (8): A538-A541, 2005 and "Columbia Forest Products Launches a Revolution in Plywood Adhesives", Environmental Building News, 14 (6) ,: 9, 2005]. However, the use of PAE or other formaldehyde-free crosslinker / soy glue systems in other wood composite applications such as particleboard, medium density fiberboard (MDF) and oriented strandboard (OSB) Low viscosity adhesive systems are required.

For particleboard, MDF and OSB, the adhesive is generally sprayed on a wood furnish and a low viscosity adhesive system is required. Since the addition of too much water causes a vapor stream during compression or requires a long compression time to remove excess water, dilution of the adhesive to a lower viscosity with additional water is of limited choice. In soy / PAE systems, one method for lower viscosity is to lower the viscosity / molecular weight of the PAE resin (US Patent Application Nos. 11 / 895,122, US20080050602A1). Another way to achieve lower viscosities while maintaining solids is to use urea as a nonvolatile denaturant / diluent to essentially lower soybean levels (US Patent Application No. 11 / 779,558, US20080021187A1). Thus, conventional systems use urea to provide good performance characteristics, but non-urea alternatives are commercially preferred.

Summary of the Invention

In an embodiment of the present invention, the adhesive composition for bonding the lignocellulosic substrate comprises a crosslinking agent (crosslinking agent) and a non-urea diluent, wherein the non-urea diluent is from about 0.01 to about based on the total wet weight of the composition Present in an amount of 75% by weight.

The invention also

(a) an aqueous mixture of proteins,

(b) crosslinking agents, and

(c) non-urea diluent, wherein the non-urea diluent is present in an amount from about 0.01 to about 75 weight percent based on the total wet weight of the composition.

It relates to an adhesive composition for bonding a lignocellulosic substrate, comprising.

The crosslinking agent contains essentially formaldehyde, typically selected from the group consisting of polyamidoamine-epichlorohydrin resins, polyamine-epichlorohydrin resins, isocyanates, epoxies, aldehyde starches, aldehydes, aldehyde resins and mixtures thereof. It is not a crosslinking agent.

The present invention also relates to a method for producing lignocellulosic composites using the adhesive composition of the present invention. The method includes applying the adhesive composition of the present invention to a lignocellulosic substrate and forming a composite by curing the adhesive composition. The type of application and the method of formation of the adhesive composition vary depending on the type of lignocellulosic composite produced. The adhesive composition is cured by heat.

The invention also relates to lignocellulosic composites produced by the process of the invention.

Surprisingly, it has been found that the addition of selected nonvolatile additives in addition to urea to adhesive formulations containing crosslinkers that are essentially free of formaldehyde can maintain good adhesive properties while providing lower formulation viscosities useful in many applications.

Detailed description of the invention

As used herein, the term "comprising" and its grammatical variations are used in the collective sense of "having" or "including" and not in the exclusive sense of "consisting of only." As used herein, the singular should be understood to encompass the singular as well as the plural.

The term "lignocellulose based" means any type of product containing lignin. Non-limiting examples include groundwood pulp, sawdust, wood particles, wood strands, wood veneers, wood boards, wood wafers, wood cladding.

In an embodiment of the present invention, the adhesive composition for bonding the lignocellulosic substrate comprises a crosslinking agent (crosslinking agent) and a non-urea diluent, wherein the non-urea diluent is from about 0.01 to about based on the total wet weight of the composition Present in an amount of 75% by weight.

In another embodiment of the invention, the adhesive composition for bonding the lignocellulosic substrate is

(a) an aqueous mixture of proteins,

(b) crosslinking agents, and

(c) non-urea diluents

Wherein the crosslinker is a crosslinker that is essentially free of formaldehyde and the non-urea diluent is present in an amount of about 0.01 to about 75 weight percent based on the total wet weight of the composition.

The protein is present in an amount of about 0.01 to about 50 weight percent, preferably 0.1 to 20 weight percent, more preferably 1 to 15 weight percent, based on the total wet weight of the composition. When calculating the percentage of protein, the protein is the actual amount of protein found in the protein source, for example soybean powder generally has about 50% by weight (based on dry matter) of the protein. Protein-based adhesives are well known in the art. Suitable protein sources for use in the present invention include casein, blood meal, feather powder, keratin, gelatin, collagen, gluten, wheat gluten (wheat protein), whey protein, zein (corn protein), rapeseed wheat (meal), sunflower wheat And soybeans.

Soybeans are a particularly useful source of protein for the present invention. Soybeans may be used in the form of soy protein isolate, soybean powder, soybean wheat or toasted soy. Soy protein is typically obtained in the form of soybean powder (about 50% by weight of protein, based on dry matter) by grinding the processed soy flakes into 100-200 mesh. Soybean powder may be further purified (typically by solvent extraction of soluble carbohydrates) to provide a soy protein concentrate containing about 65% protein by weight (dry basis). Degreased soybean can be further purified to provide soy protein isolate (SPI) having a protein content of at least about 85% by weight (based on dry matter).

Soy flours suitable for use in adhesives can be provided by removing some or most oil from soybeans and yielding a residual soybean mill that is subsequently ground to very fine soybean powder. Extrusion / extraction methods are also suitable means of oil removal, but typically hexane is used to extract most nonpolar oils from crushed soybeans. Residual hexane in the extracted soy flakes is typically removed using either a desolventiser toaster (DT) process or a flash desolventiser system (FDS). The use of the DT process (maximum temperature of about 120 ° C .; residence time of 45 to 70 minutes) results in more heat treatment to soybean than the FDS process (maximum temperature of about 70 ° C .; residence time of 1 to 60 seconds). The DT process results in a darker product, typically referred to as soy wheat or roasted soybeans. Soy wheat or roasted soybean will be used interchangeably to refer to soy products processed by the DT process.

The ability of the protein portion of the soy product to dissolve or disperse in water is measured by Protein Dispersibility Index (PDI) test. The test is carried out as follows: the soybean samples are ground, mixed with water at a certain rate and blended for a specific time (10 minutes) at a set speed (7,500 rpm). The nitrogen content of the ground soybeans and extracts is measured using the combustion method. The PDI value is the quotient of the nitrogen content of the extract divided by the nitrogen content of the original soybean.

As indicated by the lower PDI values, the protein portion of the DT-processed soybean product has lower solubility / dispersibility in water than the soy product processed by the FDS method. Soybean wheat (baked soybeans) typically has a PDI value of 20 or less, while FDS-processed soybean products have a PDI value in the range of 20-90.

Proteins used in the present invention may be pretreated or modified to improve their solubility, dispersibility and / or reactivity. For example, soy protein may be used as prepared or further modified to improve performance. US Pat. No. 7,060,798, herein incorporated by reference in its entirety, teaches methods for modifying proteins and their incorporation into adhesives.

Crosslinking agent (b) is a crosslinking agent which is essentially free of formaldehyde. The crosslinking agent may be one or more crosslinking agents selected from polyamidoamine-epichlorohydrin resins (PAE resins), polyamine-epichlorohydrin resins, isocyanates, epoxies, aldehyde starches, aldehydes, aldehyde resins and mixtures thereof. Aldehyde starches include not only dialdehyde starches, but also other starches containing aldehyde-functional groups. Aldehyde resins include glyoxal-based crosslinkers and glyoxalated polyacrylamides. Examples of useful aldehydes are glyoxal and glutaraldehyde. Examples of aldehyde functional resin crosslinkers include Sequarez® 755 (RohmNova, Mogador, Ohio), PPD M-5054® (Hercules Incorporated, Delaware, USA Wilmington), and glyoxalated polyacrylamides, such as Hercobond® 1000 (Herculis Incorporated, Wilmington, Delaware, USA). The crosslinking agent is present in an amount of about 0.01 to about 50 weight percent based on the total weight of the composition.

PAE resins are commercially available from a number of suppliers including Hercules Incorporated (Wilmington, Delaware, USA). PAE resins are prepared in a two step process, first producing polyamidoamine by polycondensation of polyalkylenepolyamines with polycarboxylic acids, typically involving the reaction of diethylenetriamine (DETA) and adipic acid. Several methods of preparing polyamidoamines that control polyamidoamine molecular weight and structure are disclosed. This includes methods for controlling molecular weight using monofunctional end capping agents, disclosed in US Pat. No. 5,786,429, US Pat. No. 5,902,862, and US Pat. No. 6,222,006, all of which are incorporated by reference. Another technique for controlling the molecular weight of polyamidoamines is discussed in US Pat. No. 6,908,983 and US Pat. No. 6,554,961.

The polyamidoamine is then reacted with epichlorohydrin in an aqueous solution to prepare a PAE resin. The preparation of thermosetting PAE resins is described in U.S. Patent 4,853,431, U.S. Patent 5,019,606, U.S. Patent 5,171,795, U.S. Patent 5,189,142, U.S. Patent 5,189,142, and U.S. Patent 5,614,597.

Glyoxal based crosslinking resins are known in the art, see for example US Pat. No. 3,869,296, US Pat. No. 3,917,659 and US Pat. No. 4,471,487. Glyoxal-urea binder compositions are described in US Pat. No. 5,435,841. U.S. Patent 5,395,440 describes glyoxal-urea binders which also contain alkali metal salts of oxygenated boronic acid and calcium hydroxide. U.S. Patent 4,284,758 discloses alkylated glyoxal / cyclic urea condensates which are formaldehyde-free crosslinking resins excellent in textile fibers. US Pat. No. 4,343,655 describes a resin in which glyoxal is reacted with cyclic urea.

Binders made from glyoxal and polyhydroxy compounds are described in US Pat. No. 5,114,999. Cyclic urea / glyoxal / polyol condensates and their use in the treatment of textile fibers and paper are described in US Pat. No. 4,455,416. Paper coating compositions containing insolubilizers for binders made from glyoxal and vicinal polyols are described in US Pat. No. 4,537,634.

Non-urea diluents (c) are low volatility, water soluble or water dispersible compounds which are low viscosity in water. Non-limiting compounds include diethylene glycol, propylene glycol, 2-methoxyethanol, glycerol and glycerol derivatives, ethylene carbonate, propylene carbonate, methyl pyrrolidone, low molecular weight polyethylene glycols and derivatives such as methoxy polyethylene glycol , Sucrose, lactose, sorbitol, maltodextrin, cyclodextrin, carbohydrates, syrups and hydrolyzed low molecular weight polysaccharides or oligosaccharides, inorganic salts such as sodium sulfate, sodium phosphate, sodium chloride and alum, bentonite, aluminosilicate, Alkali metal aluminosilicates, water soluble organic compounds such as formamide and acetamide, N-methylpyrrolidinone, surfactants, emulsifiers, oils such as vegetable oils, silicon oils, mineral oils and other oils, and mixtures thereof do.

In one embodiment of the invention, the diluent is a compound containing an alcohol function. Preferably the diluent contains a plurality of alcohol functional groups on the same molecule, such as diols and polyols.

In some embodiments of the invention, preferred non-urea diluents are glycerol, sucrose, sorbitol, corn syrup and hydrogenated corn syrup.

The non-urea diluent is present in an amount of about 0.01 to about 75 weight percent based on the total wet weight of the adhesive composition. Typically, the non-urea diluent is present in an amount of about 5 to about 60 weight percent, more typically about 10 to about 50 weight percent, based on the total wet weight of the adhesive composition.

In another embodiment, the non-urea diluent can be used with a crosslinking agent without the presence of a protein. Non-urea diluents, which act as carriers for crosslinking agents, can increase the solids of the adhesive system, as well as reduce costs. The non-urea diluent is present in an amount from about 0.01 to about 90 weight percent based on the total wet weight of the adhesive composition. U.S. Patent Application 11 / 467,669 discloses a non-protein system of azetidinium resins and urea.

In another embodiment of the present invention, one or more auxiliary additives (d) may be added to the adhesive composition of the present invention.

Auxiliary additives that may be included in the adhesive composition include extenders, viscosity modifiers, antifoams, biocides, and fillers such as flour, bark powder, nut shell powder, and corn cob flour.

The components of the adhesive composition are combined in a suitable mixer and stirred until a homogeneous mixture is obtained. Various order of additions can be used. For example, a protein source such as soybean powder may be added to the water followed by the diluent. Alternatively, a diluent can be added to water followed by a protein source. Heat treatment of the protein source / water / diluent mixture is optional. Because certain crosslinking agents may have limited stability in the formulation, the crosslinking agents are typically added near the time of application.

The adhesive composition is typically prepared at a solids content in the range of 5 to 75 weight percent, more typically in the range of 10 to 65 weight percent and most typically in the range of 20 to 60 weight percent. The most effective ratio of crosslinker to protein in the adhesive composition will depend on the substrate to which it is bound, the type of protein used and the physicochemical properties of the crosslinker. The weight ratio of protein to crosslinker used in the adhesive formulation is typically in the range of 100: 1 to 0.1: 1, more typically in the range of 25: 1 to 0.5: 1, most typically in the range of 20: 1 to 1: 1 ( Dry weight). When calculating the ratio of protein to crosslinker, the protein is the actual amount of protein found in the protein source.

The pH of the adhesive composition can be adjusted to control the reactivity of the thermosetting adhesive composition. Curing temperature and pH can be used to control the curing time that will vary with the application. The pH is typically in the range of about 5-10. For example, PAE resins are more reactive at alkaline, which is in the range of almost neutral to about pH 6-10, and will generally increase the reactivity when adjusting the pH to this range.

As mentioned above, the adhesive composition is a thermosetting material, which is cured by the application of heat and optionally pressure. Typical temperatures for curing the adhesive composition are in the range of 50 to 250 ° C, more typically in the range of 80 to 200 ° C, most typically in the range of 100 to 180 ° C. Curing times at these temperatures may range from 20 seconds to 1 hour, more typically 1 minute to 30 minutes, most typically 2 minutes to 10 minutes.

Optionally applied pressures range from approximately atmospheric pressure to about 1000 psi. Typically a pressure in the range of about 25 to about 500 psi, more typically about 25 to about 250 psi is used.

The viscosity of the adhesive composition (measured at 30 rpm with spindle 2 using a Brookfield Viscometer) is typically in the range of about 10 to about 100,000 cps, more typically in the range of about 20 to about 20,000 cps, even more Typically in the range of about 30 to about 10,000 cps. Proper viscosity depends on the particular application.

Another embodiment of the invention includes a method of making a lignocellulosic composite. The method includes applying the adhesive composition to a lignin containing substrate and curing the adhesive composition to form a lignin containing composite.

The adhesive composition of the present invention may be applied to a suitable substrate in the range of 1 to 25% by weight, preferably in the range of 1 to 12% by weight, most preferably in the range of 2 to 10% by weight, based on the total weight of the adhesive composition and the substrate. Is added.

The adhesive composition can be applied using roller coating, knife coating, extrusion, curtain coating, foam coater and spray coater, one example of which is a spinning disk resin applicator. Lower viscosity compositions in the present invention are particularly useful for spray coating and spinning disk applications such as particleboard, MDF and oriented strandboard applications.

The adhesive composition of the present invention can be used in the manufacture of hardwood plywood, particleboard, MDF and oriented strandboard. The composition is particularly useful for particleboard, MDF and oriented strandboard where lower viscosity formulations are often used.

For example, the adhesive composition may be applied onto the veneer surface by roll coating, knife coating, curtain coating, or spraying to produce plywood. Subsequently, a plurality of veneers are laminated to form a sheet having a desired thickness. The produced plates are then optionally compressed at ambient temperature to strengthen the structure (cold compression). This can be done for 1 to 10 minutes at a pressure of 25 to 250 psi. The mat or sheet is then placed on a heated press (eg a platen) and compressed to effect hardening and strengthening of the material to the board. Hardwood plywood can also be used for particleboard, oriented strand board (OSB), waferboard, fiberboard (including medium and high density fiberboard), parallel strand lumber (PSL), laminate strand lumber (LSL) and other similar It can be prepared by adhering hardwood surface veneers to a substrate such as a product.

For particleboard, MDF and oriented strandboard, the adhesive composition is generally furnished by spraying or spinning disks, followed by lamination to a face-core-face layer, followed by partial reinforcement at room temperature and final reinforcement in a heated press. Applies to The composition should be low enough in viscosity for effective spraying onto the furnish or spinning disk application. For spraying or spinning disk applications the viscosity is preferably less than 10,000 centipoise, more preferably less than 5000 centipoise.

The use of low volatility non-urea diluents allows the preparation of lower viscosity soy / crosslinker adhesive formulations at the same solids or formulations of higher solids at the same viscosity. Compared to urea, these additives have the additional advantage that there is no need to precook the soybean powder to remove urease, which leads to the formation of ammonia in the formulation with urea. In addition, certain non-urea additives, such as diols or polyols, maintain better adhesion strength when used to replace urea.

The following examples are for illustrative purposes only and are not intended to limit the claims.

Example  General way for

The following method / test was used for the examples.

(One). Brookfield viscosity (BV) was measured using a DV-II Viscometer (Brookfield Viscosity Lab, Middleboro, Mass.). A selected spindle (number 2) was attached to the instrument set at a speed of 30 RPM. The Brookfield Viscosity Spindle was placed in the formulation to allow no air bubbles to enter and then rotated at 24 ° C. for 3 minutes at the aforementioned speed. The unit is centipoise (cps).

(2) Adhesive Strength: The adhesive strength was measured using an Automated Bonding Evaluation System (ABES from AES, Inc., Kovalis, Oregon, USA). Maple veneer pieces (20 mm × 117 mm (parallel to grain) × 0.7 to 0.8 mm (thickness)) were compressed together in a lap shear configuration on the machine. The overlapping area was 5 mm, the pressure in the overlapping area was 2 MPa and the curing time was 2 minutes at 121 ° C. After curing, the samples were air cooled in the machine for 8 seconds, after which a lap shear test was performed in the machine. For wet adhesive strength, the samples were removed after compression and curing, immersed in deionized water for 1 hour at room temperature, then water was removed and the wet adhesive strength was tested in the machine. It was found that 1 hour soaking was sufficient to fully wet the binding line. Adhesive strength is expressed as breaking load (psi) per overlapped area.

(3) Particleboard panels: core furnish (internal bond testing) or face furnishing (modulus of rupture-MOR test) on rotating drums (2 ft diameter x 1 ft wide with baffles) Small panels (10 in x 10 in) were made in the laboratory by placing the. Adhesive was sprayed onto the rotating furnish using a peristaltic pump and an air spray nozzle. The panels were in the form of 10 in × 10 in plexiglass and precompressed with a metal plate. Preformed mats were compressed in a 12 in × 12 in Carver press with 11/16 in (core) or 1/2 ”(face) bars on both sides for thickness scale. Curing time Was 5 minutes at 170 ° C. For adhesion testing, the center 3 in × 3 in was cut from the cooled panel to cut nine 1 in × 1 in pieces for internal bond (IB) testing. Performed similarly to 1037-99. The weight, length, width and thickness of each piece were measured to obtain a density average. Hot melt adhesive (Cool-Lok 34-250A, National Starch Aluminum tabs were bonded to the pieces and cooled using an IB test with a Shimpo force gauge and averaged for nine samples. For testing, cut eight 8 in × 1 in pieces and ASTM D 1037-99 The MOR test was performed similarly to the span was 6 in, and the test was performed with a symphony force gauge The density was obtained by measuring the weight, length, width and thickness of each piece. A graph of MOR versus density was plotted against and the data were fitted in a straight line and normalized to 44 pcf.

Example  1 to 15

For Examples 1-13, 20 g of soybean powder (Prolia 200/20 or Prolia 100/90) were mixed with 90 g of water. The sample was then heat treated or not heat treated. The heat treatment consisted of heating the soybean mixture at 80 ° C. for 30 minutes, cooling to 50 ° C. and holding at 50 ° C. for 1 hour. Diluent (40 g) was then added to the soybean mixture with 0.1% Proxel® GXL (Arch Chemicals, Norwalk, Conn., USA) as an antiseptic (except Example 1). Except where indicated, the total solids for the examples were 40%. Soybean powder formulations with soybean oil (Example 13) were prepared by stirring the mixture at 23 ° C. for 5 minutes to form a stable emulsion. The viscosity was measured at 30 rpm with spindle 2 using a Brookfield viscometer. The data is shown in Table 1.

The viscosities listed in Table 1 indicate that Examples 1-13 are low viscosity flowable formulations. The finished adhesive composition of the present invention could be prepared by simply adding a crosslinking agent to provide a low overall viscosity. In contrast, the 40% solids mixture only of soy flour and water (Example 14, no diluent) was high in viscosity and did not flow at all. To obtain a similar viscosity without diluent, the solids level had to be nearly 13.3% (Example 15). The viscosity when using the diluent of the present invention (Examples 2 to 13) was lower than the viscosity when using urea as the diluent (Example 1).

Example  16 to 28

Examples 16-27 used the soybean + diluent mixtures of Examples 1-11 and 15. Example 16 is the urea control and Example 27 is the non-diluent control. Example 28 For each example except (no PAE), 10% PAE resin crosslinker (Chemvisions CA1000, 100 cps, Hercules Incorporated) based on resin solids on soybean + diluent solids ) Was mixed with the soybean + diluent mixture on the day of the ABES test. For example, for each 100 gm of soy + diluent solids, 10 g of PAE solids were added. The pH of CA1000 was adjusted to 6.5-7.0 with 10% NaOH before use. Adhesion strength was observed for up to 11 days as an indicator of stability of the soybean + diluent mixture. Dry and wet adhesion results (ABES) are listed in Table 2 in psi. Example 28 shows that very small wet adhesion is provided by soy flour without crosslinker. The remaining examples were crosslinker (PAE).

The data listed in Table 2 show that diluents other than urea can maintain wet and dry adhesion equal to or better than urea compared to controls without additives. The results unexpectedly show that conventional techniques rely on the use of urea to lower viscosity and maintain strength. Sucrose and glycerol worked well with 200/20 soybean powder (heated and unheated) as well as 100/90 powder (heated). Sodium chloride caused a large decrease in adhesion, while other salts such as sodium sulfate could maintain adhesion. Adhesion of the mixture of soybean and sucrose and glycerol maintained good performance for more than 10 days. It was also a low viscosity solution at high solids (Table 1).

Example  29 to 33

Examples 29-33 used soybean oil and a combination of sodium sulfate or sodium chloride and glycerol as diluent. Example 29 was urea prepared as in Example 1. For Example 30, 13.3 g of Prolia 100/90 was mixed with 26.7 g of soybean oil and 60 g of water. For Example 31, 13.3 g Prolia 100/90 was mixed with 13.3 g glycerol, 13.3 g NaCl and 60 g water. For Example 32, 13.3 g Prolia 100/90 was mixed with 13.3 g glycerol, 13.3 g sodium sulfate and 60 g water. For Example 33, 22 g Prolia 100/90 were mixed with 12 g glycerol, 12 g sodium sulfate and 54 g water. For Examples 29-33, 1 g PAE resin crosslinker solids (Chemvisions CA1000, Hercules Incorporated) were mixed with 10 g soy + diluent solids on the day of the ABES test. Dry and wet adhesion results (ABES) are listed in Table 3 in psi.

Example 30 shows that the wet adhesion with soybean powder / soybean oil emulsion in the series of evaluations improved compared to the wet adhesion of the urea / soybean powder combination (Example 29). Example 31 shows that very small wet adhesion is provided by glycerol and soybean powder with sodium chloride. Examples 32 and 33 show that the glycerol-sodium sulfate combination provides much better adhesion performance than the glycerol-sodium chloride combination.

Example  34 to 39

Examples 34-39 describe the preparation of particleboard panels using various formulations of the present invention, as well as urea-containing controls. Table 4 shows the adhesive formulation as well as the obtained panel density and IB data. A 7.25% adhesive (solids to solids basis) was sprayed onto the wood furnish for each panel. In all cases the diluent / soybean was 2: 1 (solids to solids basis). Examples 34-35 were heat treated as in Example 16, while Examples 36-39 using Prolia 100/90 soybean powder were not heat treated as in Example 24. No pH adjustment was made for the adhesive formulation or crosslinker except for adjusting the adhesive to pH 10 for Example 39.

The table describes the ability to produce particleboard at high solids using a glycerol diluent. Cooking / heat treatment of the formulation was not necessary. Surprisingly, the internal bond strength of the glycerol formulations was higher than that for urea-containing formulations at similar panel densities.

Example  40

Example 40 (Table 5) describes embodiments of the invention without protein. The adhesive mixture was 200 g PAE resin (CA1300, 30% solids) + 180 g glycerol. Viscosity was measured at 30 rpm with spindle # 2. Particleboard was made with a face furnish followed by a MOR test. A 10.8% adhesive was sprayed onto the furnish. A good panel was generated where the MOR was equivalent to the MOR (1855 psi) of the urea-formaldehyde resin + catalyst control.

Example  41

This example illustrates the use of non-urea diluents and low PDI powders to produce mixtures of high solids that can be used with crosslinking agents. Glycerol, water and ADM KaySoy (baked soybean) were mixed with a glycerol / soybean ratio of 2/1 and 66% total solids to give a homogeneous product with a viscosity (spindle 4, 30 rpm) of 6160 cps. .

The foregoing description illustrates and describes the present invention. In addition, the foregoing disclosure merely illustrates and describes preferred embodiments of the present invention, but as mentioned above, it is possible for variations or modifications within the scope of the concept as expressed herein, which is to be taught and / or Or understand the skills or knowledge of the industry concerned. The embodiments described above also describe the best mode known to practice the invention and to enable one skilled in the art to use the invention in these or other embodiments or in combination with the various modifications required for the particular application or use disclosed herein. It is intention. Accordingly, the description is not intended to limit the invention to the form disclosed herein. Also, it is intended that the appended claims be understood to cover alternative embodiments.

As each individual publication, patent, or patent application is specifically and individually incorporated by reference, all publications, patents, and patent applications cited herein are incorporated herein by reference for any or all purposes. In case of inconsistency, the present application will control.

Claims (19)

Crosslinkers essentially free of formaldehyde, and
Non-urea diluent present in an amount of about 0.01 to about 75 weight percent based on the total wet weight of the composition
Adhesive composition comprising a. The adhesive composition of claim 1 further comprising an aqueous mixture of protein sources. The adhesive composition of claim 2 wherein the aqueous mixture of protein sources is obtained from a mixture of water and one or more products selected from the group consisting of soybean powder, soy protein concentrate, soy protein isolate, and mixtures thereof. The adhesive composition of claim 1, wherein the crosslinking agent is selected from the group consisting of polyamidoamine-epichlorohydrin resins, polyamine-epichlorohydrin resins, isocyanates, epoxies, aldehyde starches, aldehydes, aldehyde resins and mixtures thereof. The non-urea diluent of claim 1, wherein the non-urea diluent is diethylene glycol, propylene glycol, 2-methoxyethanol, glycerol, glycerol derivatives, ethylene carbonate, propylene carbonate, methyl pyrrolidone, low molecular weight polyethylene glycols and derivatives Such as methoxy polyethylene glycol, sucrose, lactose, sorbitol, maltodextrin, cyclodextrin, carbohydrates, syrups and hydrolyzed polysaccharides, inorganic salts, sodium sulfate, sodium phosphate, sodium chloride, alum, bentonite, aluminosilicate, alkali Adhesive composition which is at least one diluent selected from the group consisting of metal aluminosilicates, water soluble organic compounds, formamides, acetamides, N-methylpyrrolidinones, surfactants, emulsifiers, oils, vegetable oils, silicon oils and mineral oils . The adhesive composition of claim 2 wherein the non-urea diluent is selected from the group consisting of glycerol, sucrose, corn syrup, sorbitol, hydrogenated corn syrup, and mixtures thereof. The adhesive composition of claim 2, wherein the protein in the protein source is present in an amount from about 0.01% to about 50% by weight based on the total wet weight of the adhesive composition. The adhesive composition of claim 2, wherein the crosslinking agent is present in an amount from about 0.01% to about 50% by weight based on the total wet weight of the adhesive composition. The adhesive composition of claim 2, wherein the non-urea diluent is present in an amount of about 5 to about 60 weight percent based on the total wet weight of the adhesive composition. The adhesive composition of claim 2, wherein the crosslinker is polyamidoamine-epichlorohydrin. The adhesive composition of claim 2 wherein the solids content is from about 5 to about 75 weight percent. The adhesive composition of claim 2 wherein the weight ratio of protein to crosslinker is from about 100: 1 to about 0.1: 1. A method of making a lignocellulosic composite comprising applying the adhesive composition of claim 2 to a lignocellulosic substrate and curing the adhesive composition to form a lignocellulosic composite. The method of claim 13, wherein the adhesive composition is applied to the lignocellulosic substrate at a concentration of about 1 to about 25 weight percent based on the total weight of the adhesive composition and lignocellulosic substrate. The method of claim 13, wherein a pressure in the range of about atmospheric pressure to about 1000 psi is applied during curing. The method of claim 13, wherein the adhesive composition is cured at a temperature of about 50 to about 250 ° C. The method of claim 13, wherein the lignocellulosic substrate is at least one substrate selected from the group consisting of groundwood pulp, sawdust, wood particles, wood strands, wood veneers, wood boards, wood wafers, and wood coatings. Lignocellulosic complex obtained from the method of claim 13. 19. The ligno of claim 18 selected from the group consisting of hardwood plywood, particleboard, medium density fiberboard, oriented strandboard, waferboard, fiberboard, parallel strand lumber, laminate strand lumber and hardwood veneer products. Cellulose complex.